The major goal of the Cell Biology Core is to facilitate the use of quantitative qualitative imaging techniques and in the analysis of transport processes at the cellular and molecular level. The range of imaging techniques which are applicable to the study of cells, tissues, whole organs and in wild type, transgenic and mutant animals have been greatly expanded. New technologies are now available for greater resolution of localization of specific target proteins as well as permitting vital microscopy where dynamic changes can be identified. These include immunocytochemistry, confocal microscopy, electron microscopy, in situ hybridization, uunbiased stereological morphometry, and vital microscopy. These techniques are extremely useful in cell biology and physiology but are not easily accessible to investigators without previous training or experience. In addition, the selection of the proper technique or combination of techniques requires experience in interpetation and knowledge of the limitations of the method. The core will provide expertise and assistance in the utilization of light, immunofluorescence, confocal, and electron microscopy with particular emphasis on phenotypic and pathologic analysis of transgenic models, immunocytochemistry, vital microscopy and image analysis. The facility will give access to these specialized techniques and to the equipment necessary to apply them and will form a focal point for collaboration between members of the program project. Specifically, the core will provide the facilities, service and education necessary for the efficient application of imaging techniques tailored to the individual research objectives of the various members.